@Invader:
Why? What logical reason can there be for considering homosexuality as a great evil?
Um, the verse I posted earlier?
9 Do you not know that the wicked will not inherit the kingdom of God? Do not be deceived: Neither the sexually immoral nor idolaters nor adulterers nor male prostitutes nor homosexual offenders 10 nor thieves nor the greedy nor drunkards nor slanderers nor swindlers will inherit the kingdom of God. - 1 Corinthians 6:9-10
I'm sexually immoral, I'm an adulterer, and I'm a slanderer. The point is, I'm forgiven by Christ's death on the cross, and while I am still these things, I can no longer live the life of them. Can I be a liar and a Christian? Yes, but I can no longer live the life of a liar. Can I be an adulterer and be a Christian? Yes, but I can no longer live the life of an adulterer. Can I be a homosexual and be a Christian? Yes, but I can no longer live the life of a homosexual.
You say what is the logical reason. That depends on your bias. You are biased that Christianity is false; therefore, any logic we use will be illogical to you. By the same token, we are biased that Christianity is true; therefore, any logic you use will be illogical to us. But the Bible says that too:
@1:
18 For the message of the cross is foolishness to those who are perishing, but to us who are being saved it is the power of God. 19 For it is written:
"I will destroy the wisdom of the wise;
the intelligence of the intelligent I will frustrate."
20 Where is the wise man? Where is the scholar? Where is the philosopher of this age? Has not God made foolish the wisdom of the world? 21 For since in the wisdom of God the world through its wisdom did not know him, God was pleased through the foolishness of what was preached to save those who believe. 22 Jews demand miraculous signs and Greeks look for wisdom, 23 but we preach Christ crucified: a stumbling block to Jews and foolishness to Gentiles, 24 but to those whom God has called, both Jews and Greeks, Christ the power of God and the wisdom of God. 25 For the foolishness of God is wiser than man's wisdom, and the weakness of God is stronger than man's strength. 26 Brothers, think of what you were when you were called. Not many of you were wise by human standards; not many were influential; not many were of noble birth. 27 But God chose the foolish things of the world to shame the wise; God chose the weak things of the world to shame the strong. 28 He chose the lowly things of this world and the despised things—and the things that are not—to nullify the things that are, 29 so that no one may boast before him. 30 It is because of him that you are in Christ Jesus, who has become for us wisdom from God—that is, our righteousness, holiness and redemption. 31 Therefore, as it is written: "Let him who boasts boast in the Lord."
The point to us is, God says it's wrong. Since He says it's wrong, and He cannot be wrong, because He is God, then it's wrong. Doesn't matter if it makes sense to us or not. He's infinitely smarter than we could ever be.
Again, I know you don't buy this, so to you, this isn't a logical reason at all, but to us who accept God is holy, it makes perfect logical sense.
EDIT: Eh, I'll just address this real quick, hopefully in the most mature way I can.
@Invader:
The only real reason that Christians consider homosexuality to be a sin anymore is a deep disliking, or even hatred, towards a fellow human being, or just plain ignorance.
Have I ever stated that I dislike or hate homosexuals? No, in fact, I tend to get angry and irritated at any Christian who preaches hatred to them. We are to be like Christ, who reached out to, hung out with, people who were considered horrible people in their day, Gentiles and tax collectors. In fact, most of the Pharisees sneered and condemned Jesus BECAUSE he hung around these people that were considered the dregs of society.
Jesus wouldn't condemn homosexuals, He wouldn't treat them like animals, He wouldn't put them down, you know what He would do? He would hang out with them, be their friends, treat them like the wonderful creations of God that they are. Would he approve of their sin? No, Jesus never approved of anyone's sin, but neither did He condemn them or treat them poorly. In fact, He did just the opposite, pointing out everyone's faults in love.
Remember the woman who was going to get stoned for adultery? Remember how Jesus turned away the crowd by saying that whoever was without sin was to cast the first stone? Know what happened after that?
9 At this, those who heard began to go away one at a time, the older ones first, until only Jesus was left, with the woman still standing there. 10 Jesus straightened up and asked her, "Woman, where are they? Has no one condemned you?" 11 "No one, sir," she said.
"Then neither do I condemn you," Jesus declared. "Go now and leave your life of sin." - John 8:9-11
Jesus didn't approve of her sin, but He didn't condemn her. He simply told her, "Leave your life of sin."
I also fail to see how we are considered ignorant for simply following the beliefs of our religion. I admit, a lot of Christians use this doctrine to persecute and harass homosexuals, and know what? They're wrong. They're COMPLETELY and totally wrong and have NO excuse in God's eyes to treat homosexuals like they do. But believing it's wrong, and still treating them like people, fallen people like myself, and being their friend and treating them with love and respect, I don't see how that's ignorant.